Hydraulic tool latch bracket

ABSTRACT

A latch bracket for attachment to a hydraulically operated tool having a hydraulic mechanism, the latch bracket includes a first fluid channel extending therethrough, with a first port coupled to the first fluid channel for coupling the first fluid channel to the hydraulic mechanism. The latch bracket receives a male latch pin on a tool coupler to lock the tool to the tool coupler and to couple the first fluid channel to a source of hydraulic pressure through the latch pin.

This is a divisional application of U.S. application Ser. No.09/124,637, filed Jul. 29, 1998, the entire disclosure of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

The invention relates to fluid connectors, and, in particular, to amulti-line hydraulic connector adapted for se in a tool coupler usedwith excavation, demolition and construction equipment.

Some types of construction equipment, such as backhoes or excavators,include a movable dipper stick (also referred to as an arm) to which avariety of tools, such as buckets, grapples, hammers and the like, canbe attached. A hydraulic bucket cylinder coupled to the attached tool ata link pivot rotates the tool about a dipper pivot at the free end ofthe dipper stick. The bucket cylinder and a linkage to the link pivotare located on a distal (forward) side of the dipper stick relative tothe cab where the operator sits. To simplify the process of changingtools, a tool coupler can be permanently attached to the dipper pivotand the link pivot. A selected tool can then be removably attached tothe coupler with a locking mechanism. The locking mechanism, in somecases, includes a locking pin on the tool coupler that engages a matingreceptacle in the tool.

There is a trend in the industry to use an actuated quick-disconnecttool coupler for automatically connecting and disconnecting a tool.Co-owned U.S. Pat. No. 5,727,342, to Horton, describes aquick-disconnect tool coupler that includes a latch pin biased by aspring to a forward locking position. The latch pin is retracted byextending a hydraulic latch pin cylinder located in the coupler. Withthis type of tool coupler, the equipment operator can switch toolswithout leaving the cab of the equipment.

Some tools include a hydraulically actuated mechanism. For example, somegrapple attachments include a hydraulic cylinder for opening and closingthe grapple jaws. The tool hydraulics typically require two hydraulicconnections between the tool hydraulics and hydraulic lines extending tothe end of the dipper stick. In presently available systems, theseconnections must be made manually. This reduces the efficiencies of thehydraulically actuated quick-disconnect tool coupler systems, becausethe equipment operator must leave the cab to make the connections or asecond worker must be available to do so.

SUMMARY OF THE INVENTION

The invention features a non-spill, multi-line fluid connector with aplurality of separate, substantially coaxial flow paths. The fluidconnector can be incorporated into a latch pin assembly of aquick-connect tool coupler.

The connector design does not compromise the latching mechanism of thequick coupler. The latching mechanism includes a latch pin in the toolcoupler and a latch bracket that receives the latch pin in the tool. Thelatch pin is spring applied, and hydraulically released from the latchbracket. Each of the latch pin and latch bracket includes longitudinallymovable internal parts that provide a pair of coaxial fluid channels.These parts cooperate when the latch pin is inserted into the latchbracket to provide connections between the pairs of channels. Theinvention allows tools and existing couplers to be easily converted tothe new system. An equipment operator can connect a hydraulicallyactuated tool to the tool coupler, including all hydraulic connections,without leaving the cab of the equipment. The fluid connector includes alocking mechanism that enhances the overall safety of the equipment byinhibiting accidental release of the hydraulic tool when pressure ishydraulic pressure is applied to hydraulic actuator in the tool.

According to one aspect of the invention, a fluid connector includes afirst part having a distal end and a second part having a proximal endadapted to be removably connected to the distal end of the first part.The first part includes first and second fluid channels extending withinthe first part from respective first and second end seals at the distalend and couple to respective first and second fluid ports. The end sealsclose off the first and second fluid channels when the first part isdisconnected from the second part. The second part includes first andsecond fluid channels extending within the second part from respectivefirst and second end seals at the proximal end and couple to respectivefirst and second fluid ports. The end seals of the second part close offthe first and second fluid channels of the second part when the firstpart is disconnected from the second part. Connecting the first part tothe second part connects the first fluid channels of the first andsecond parts and also connects the second fluid channels of the firstand second parts.

The first and second fluid channels of one or both of the first part andthe second part can be arranged concentrically. With this feature, thefirst and second parts are cooperatively structured to permit the firstand second parts to rotate relative to each other while connectedtogether. In one embodiment, the second fluid channel of the first partincludes an outer channel arranged concentrically around the inner,first channel of the first part, and the second fluid channel of thesecond part includes an outer channel arranged concentrically around theinner channel of the second part. The inner channel of the first partcan be a central channel arranged on a central axis of the first part.

The first and second parts can be adapted to connect together withmake-before-break seals such that the first end seal of one of the firstand second parts establishes a seal with the other of the first andsecond parts before the first end seal of the other of the first andsecond parts opens, and such that the second end seal of the one of thefirst and second parts establishes a seal with the other of the firstand second parts before the second end seal of the other of the firstand second parts opens.

The first part can be constructed to include the following features: Anelongated pin body has a central bore extending from the distal end tonear a proximal end, and a pin head at the proximal end of the pin body.The pin head includes the first and second ports of the first part,wherein first and second connecting channels communicate between thefirst and second ports, respectively and the central bore. The bore hasa pin central opening surface, which includes, at a distal end, acylindrical distal portion and a tapered portion sloping radially inwardtoward the cylindrical distal portion, and which also includes, at aproximal end, a cylindrical proximal portion having a smaller diameterthan the cylindrical distal portion of the pin central opening surface.The cylindrical distal portion and the tapered portion of the pincentral opening surface can be on a pin outer sleeve that issubstantially fixed in position at a distal end of the pin body. Thefirst part also includes a tube having a proximal outer surfacepositioned adjacent the cylindrical proximal portion of the pin centralopening surface. The tube is positioned such that it divides between thecentral channel and the outer channel. The first connecting channelcommunicates with the central channel and the second connecting channelcommunicates with the outer channel. A pin proximal seal is arranged toprovide a seal between the proximal outer surface of the tube and thecylindrical proximal portion of the pin central opening surface. A pininner sleeve includes a cylindrical surface at a proximal end adapted toslide along a cylindrical surface at a distal end of the tube. An outersurface of the pin inner sleeve has a cylindrical distal portion adaptedto slide along the cylindrical distal portion of the pin central openingsurface, and a tapered portion adapted to fit against the taperedportion of the pin central opening surface. An inner surface of the pininner sleeve has a cylindrical distal portion and a tapered portionsloping radially inward toward the cylindrical distal portion of theinner surface of the pin inner sleeve. The second end seal of the firstpart includes a seal located between the cylindrical distal portion ofthe outer surface of the pin inner sleeve and the cylindrical distalportion of pin central opening surface. A pin outer bias member isarranged to urge the tapered portion of the outer surface of the pininner sleeve against the tapered portion of the pin central openingsurface. A pin middle seal is arranged to provide a seal between thecylindrical surface at the proximal end of the pin inner sleeve and thecylindrical surface at the distal end of the tube. A plug has acylindrical distal surface adapted to slide along the cylindrical distalportion of the inner surface of the pin inner sleeve, and a taperedsurface adapted to fit against the tapered portion of the inner surfaceof the pin inner sleeve. The first end seal of the first part is locatedbetween the cylindrical distal surface of the plug and the cylindricaldistal portion of the inner surface of the pin inner sleeve. A pin innerbias member is arranged to urge the tapered portion of the outer surfaceof the plug against the tapered portion of the inner surface of the pininner sleeve. Thus, in this arrangement of the first part, the centralchannel is defined by an inner surface of the tube, the inner surface ofthe pin inner sleeve, the plug, and the first end seal of the firstpart. The outer channel of the first part is defined by the pin centralopening surface, the outer surface of the tube the outer surface of thepin inner sleeve, and the second end seal. The pin proximal seal and thepin middle seal provide seals between the central channel and the outerchannel.

The second part can include one or more of the following additionalfeatures. An elongated plunger extends proximally from a bracket body afirst distance and has an outwardly sloped surface near a proximal end.A substantially annular inner section member extends proximally from thebracket body a second distance that is less than the first distance. Theinner section member is arranged substantially concentrically around theplunger and includes a cylindrical surface. A substantially annularouter section member extends proximally from the bracket body a thirddistance that is less than the first distance and greater than thesecond distance. The outer section member is arranged concentricallyaround the inner section member and includes a cylindrical surface. Abracket inner sleeve has an inner surface with an outwardly slopedportion at a proximal end adapted to fit against the outwardly slopedsurface of the plunger. The bracket inner sleeve also has an outersurface with an outwardly sloped portion near a distal end, and acylindrical surface at a distal end that slidingly engages with thecylindrical surface of the inner section member. The end seal of theinner channel of the second part is provided between the outwardlysloped portion of the inner surface of the bracket inner sleeve and theoutwardly sloped surface of the plunger. The inner channel of the secondpart, which is substantially annular shape, is defined by the plunger,an inner surface of the inner section member and the inner surface ofthe inner sleeve. A bracket inner middle seal is arranged to sealbetween the cylindrical surface of the inner section member and thecylindrical surface of the bracket inner sleeve. A bracket second sleevehas an inner surface having an outwardly sloped portion at a proximalend adapted to fit against the outwardly sloped surface of the outersurface of the inner sleeve, and a cylindrical surface at a distal endthat slidingly engages with the cylindrical surface of the inner sectionmember. The end seal of the outer channel of the second part is providedbetween the outwardly sloped portion of the inner surface of the bracketsecond sleeve and the outwardly sloped surface of the outer surface ofthe bracket inner sleeve. The outer channel of the second part isdefined by an outer surface of the inner section member, an outersurface of the bracket inner sleeve, the inner surface of the bracketsecond sleeve, and an inner surface of the outer section member. Thebracket inner middle seal seals between the inner channel and the outerchannel of the first part. A bracket outer middle seal is arranged toseal between the cylindrical surface of the outer section member and thecylindrical surface of the bracket second sleeve. A bracket bias memberis arranged to urge the bracket second sleeve proximally against thebracket inner sleeve and the bracket inner sleeve against the plunger.

In addition, the bracket body can further include a cylindrical bearingat a proximal end adapted to receive the pin body such a distal face ofthe plug first contacts a proximal face of the plunger when the pin bodymoves distally through the cylindrical bearing. The outer surface of thebracket inner sleeve can also include, at its proximal end, acylindrical proximal portion that is approximately the same diameter asthe cylindrical surface of the plug. Thus, upon further movement of thepin body through the cylindrical bearing in the distal direction, theplug is prevented from further distal movement, the cylindrical distalportion of the inner surface of the pin inner sleeve slides over thecylindrical proximal portion of the outer surface of the bracket innersleeve, and a gap opens between the inwardly sloped surface of the plugand the inwardly sloped portion of the inner surface of the pin innersleeve. The first end seal of the first part may include an inner distalo-ring that slides with the pin inner sleeve over the cylindricalproximal portion of the outer surface of the bracket inner sleeve.

An outer surface of the bracket second sleeve can have, at a proximalend thereof, a cylindrical proximal portion approximately the samediameter as the cylindrical distal portion of the pin central openingsurface. With this arrangement, upon yet further movement of the pinbody through the cylindrical bearing in the distal direction, a distalfacing surface of the pin inner sleeve stops against a proximal facingportion of the outer surface of the bracket inner sleeve, thecylindrical distal portion of the pin central opening surface slidesover the cylindrical proximal portion of the outer surface of thebracket second sleeve, and a gap opens between inwardly sloped portionsof the pin central opening surface and the outer surface of the pininner sleeve. The second end seal of the first part includes an outerdistal o-ring that slides with the pin body over the cylindricalproximal portion of the outer surface of the bracket second sleeve. Thepin inner bias member, the pin outer bias member, and the bracket biasmember can be selected such that the first and second end seals of thesecond part remain sealed, such that the central channel and outerchannel of the first part remain closed, and such that the inner channeland the outer channel of the second part remain closed, as the outerdistal o-ring slides over the cylindrical proximal portion of the outersurface of the bracket second sleeve. Upon yet more distal movement ofthe pin body through the cylindrical bearing, a distal end of the pinbody contacts a proximal facing portion of an outer surface of thebracket second sleeve, and pushes the bracket second sleeve and thebracket inner sleeve together distally such that the bracket innersleeve slides distally away from the outwardly sloped surface of theplunger. This opens the first end seal of the second part and connectsthe inner channel of the second part to the central channel of the firstpart, until the distal end of the bracket inner sleeve reaches aproximal facing stop surface that prevents further distal movement ofthe pin inner sleeve while the bracket second sleeve continues to movedistally. The continued distal movement of the bracket second sleeveopens the second end seal of the second part and connects the outerchannel of the second part to the outer channel of the first part.

In other features, the second part may further include a lockingmechanism that inhibits the pin body from moving away from the secondpart while fluid pressure is applied through the first part and thesecond part. The first part can include a fluid switch arranged to turnon to weakly couple fluid pressure in the central channel with fluidpressure in the outer channel when the first part is disconnected fromthe second part, and to turn off to decouple fluid pressure in thecentral channel with fluid pressure in the outer channel when the firstpart is connected to the second part. The second part may also include afluid switch arranged to turn on to weakly couple fluid pressure in theinner channel with fluid pressure in the outer channel when the firstpart is disconnected from the second part, and to turn off to decouplefluid pressure in the inner channel with fluid pressure in the outerchannel when the first part is connected to the second part. The secondpart can have a distal end cap, which includes the first and secondports of the second part, a first connecting channel communicatingbetween the first port and the inner channel of the second part, and asecond connecting channel communicating between the second port and theouter channel of the second part. The second part may also have abacking piece, which includes the inner section member, the outersection member and an opening there-between. The backing piece iscapable of moving a small lateral distance from a central axis of thesecond part.

In another aspect, the invention provides a latch member, such as alatch pin, for a tool coupler, adapted to engage with a latchreceptacle, such as a latch bracket, on a tool to lock the tool to thetool coupler. The latch member may include one or a plurality of fluidchannels. The plurality of fluid channels can include first and secondfluid channels, extending through the latch member for providing acorresponding plurality of fluid connections to the tool through thelatch receptacle. The second fluid channel can be an outer fluid channelconcentrically surrounding the first fluid channel, and the first fluidchannel can be a central fluid channel extending along a central axis ofthe latch member. A first distal o-ring provides a seal at a distal endof the central channel and a second distal o-ring provides a seal at adistal end of the outer channel when the latch member is disconnectedfrom the latch receptacle. The first and second distal o-rings arelocated near a distal end of the latch member that connects to the latchreceptacle.

An embodiment of the latch pin is adapted to slidingly engage with thelatch bracket. The latch pin can further include an elongated pin bodythat has a central opening extending from a distal end of the latch pinto a proximal end of the latch pin. The central opening has a centralopening surface, which includes, at a distal end, a cylindrical distalportion and a tapered portion sloping radially inward toward thecylindrical distal portion, and which also includes, at a proximal end,a cylindrical proximal portion having a smaller diameter than thecylindrical distal portion of the pin central opening surface. Thecylindrical distal portion of the central opening surface includes ano-ring groove in which the second distal o-ring is positioned. Thecylindrical distal portion and the tapered portion of the pin centralopening surface can be part of an outer sleeve substantially fixed inposition at a distal end of the pin body. A tube divides between thecentral channel and the outer channel. The tube includes an outersurface having a proximal portion positioned adjacent the cylindricalproximal portion of the pin central opening surface. A proximal o-ringseals between the proximal portion of the tube outer surface and thecylindrical proximal portion of the pin central opening surface. A firsthydraulic fluid port couples to the central channel on a proximal sideof the proximal o-ring, and a second hydraulic fluid port couples to theouter fluid channel on a distal side of the proximal o-ring. An innersleeve includes, at a proximal end of an inner surface, a cylindricalsurface that is adapted to slide along a cylindrical surface at a distalend of the tube, which cylindrical surface can be on the outer surfaceof the tube. The inner sleeve also has an outer surface, which includesa cylindrical distal portion adapted to slide along the cylindricaldistal portion of the pin central opening surface. The second distalo-ring provides a seal therebetween. The outer surface of the innersleeve has a tapered portion adapted to fit against the tapered portionof the pin central opening surface. The inner sleeve has an innersurface that includes a cylindrical distal portion and a tapered portionsloping radially inward toward the cylindrical distal portion of theinner surface of pin inner sleeve. The cylindrical distal portion of theinner sleeve inner surface includes an o-ring groove in which the firstdistal o-ring is positioned. An outer bias member is arranged to urgethe tapered portion of the outer surface of the pin inner sleeve againstthe tapered portion of the pin central opening surface. A middle o-ringis arranged to provide a seal between the cylindrical surface at theproximal end of the pin inner sleeve and the cylindrical surface at thedistal end of the tube. An plug includes a cylindrical distal surfaceadapted to slide along the cylindrical distal portion of the innersurface of the pin inner sleeve. The first distal o-ring provides a sealtherebetween. The plug also has a tapered surface adapted to fit againstthe tapered portion of the inner surface of the pin inner sleeve. Aninner bias member is arranged to urge the tapered portion of the outersurface of the plug against the tapered portion of the inner surface ofthe pin inner sleeve. In this structure, the central channel is definedby an inner surface of the tube, the inner surface of the pin innersleeve, the plug, and the first distal o-ring. The outer channel isdefined by the pin central opening surface, the outer surface of thetube, the outer surface of the pin inner sleeve, and the second distalo-ring. The proximal o-ring and the middle o-ring seal between thecentral channel and the outer channel.

The inner bias member can be an inner coil spring positioned between aproximal facing shoulder of an inner surface of the tube and a proximalfacing end of the plug. The outer bias member can be an outer coilspring positioned between a proximal facing shoulder formed on thecentral opening surface and a distal facing shoulder formed on the outersurface of the inner sleeve.

The latch member can further include a fluid switch between the centralchannel and the outer channel that is closed circuit when the latchmember is disconnected from the latch receptacle to equalize pressuresbetween the central channel and the outer channel, and that is opencircuit when the latch member is connected to the latch bracket to allowfor a pressure difference between the central channel and the outerchannel. The fluid switch can include a small aperture in the innersleeve that is located on a distal side of the middle o-ring when theswitch is closed circuit and that is positioned on a proximal side ofthe middle o-ring when the switch is open circuit.

The latch member can be in combination with the tool coupler. The toolcoupler includes a hydraulic latch member actuating mechanism adapted tomove the latch member under hydraulic control between a position lockedwith the latch receptacle and a position unlocked from the latchreceptacle. The hydraulic latch member actuating mechanism can include aspring arranged to urge the latch member into the locked position and ahydraulic cylinder having an extendable rod arranged to urge the latchmember toward the unlocked position when the rod is extended.

In yet another aspect, the invention provides a latch bracket forattachment to a hydraulically operated tool having a hydraulicmechanism. The latch bracket includes at least a first, and may includea second, fluid channel extending therethrough. The latch bracket isadapted to receive a male latch pin on a tool coupler to lock the toolto the tool coupler and to couple the fluid channels to sources ofhydraulic pressure through the latch pin. First and second ports arecoupled to the first and second fluid channels, respectively, forcoupling the fluid channels to the hydraulic mechanism. The second fluidchannel can be an outer fluid channel concentrically surrounding thefirst fluid channel, and the first fluid channel can be a substantiallyannular inner fluid channel. An inner proximal o-ring provides a seal ata proximal end of the inner channel and an outer proximal o-ringprovides a seal at a proximal end of the outer channel when the latchpin is disconnected from the latch bracket. The first and secondproximal o-rings are arranged to unseal when the latch pin connects tothe latch bracket.

The latch bracket can include the following additional features. A latchbracket body has a cylindrical bearing at a proximal end adapted toreceive and guide the latch pin, and an end cap at a distal end. Anelongated plunger extends proximally from the body a first distance. Theplunger includes an outwardly sloped surface near a proximal end, and aproximal end face that first contacts a distal end of the latch pin whenthe latch pin is inserted into the cylindrical bearing. The outwardlysloped surface has an o-ring groove in which the inner proximal o-ringis positioned. A substantially annular inner section member extendsproximally from the body a second distance that is less than the firstdistance. The inner section member includes a cylindrical surface and isarranged substantially concentrically around the plunger, providing agap therebetween. A substantially annular outer section member extendsproximally from the body a third distance that is less than the firstdistance and greater than the second distance. The outer section memberincludes a cylindrical surface and is arranged concentrically around theinner section member, providing a gap therebetween. The inner sectionmember and the outer section member can be embodied in a single backingpiece, and the gap can be provided by one or more openings in thebacking piece. The backing piece is capable of moving a small lateraldistance from a central axis of the latch bracket. An inner sleeveincludes an inner surface having an outwardly sloped portion at aproximal end adapted to fit against the outwardly sloped surface of theplunger. The first proximal o-ring provides a seal therebetween when thelatch bracket is disconnected from the latch pin. The inner sleeve alsoincludes an outer surface having an outwardly sloped portion near adistal end that includes an o-ring groove in which the outer proximalo-ring is positioned, and a cylindrical surface at a distal end thatslidingly engages with the cylindrical surface of the inner sectionmember. A inner middle o-ring provides a seal between the cylindricalsurface of the inner section member and the cylindrical surface of thebracket inner sleeve. The bracket also includes a second sleeve, whichhas an inner surface having an outwardly sloped portion at a proximalend adapted to fit against the outwardly sloped surface of the outersurface of the inner sleeve. The outer proximal o-ring provides a sealtherebetween when the latch bracket is disconnected from the latch pin.The second sleeve also has a cylindrical surface at a distal end thatslidingly engages with the cylindrical surface of the inner sectionmember. An outer middle o-ring is arranged to seal between thecylindrical surface of the outer section member and the cylindricalsurface of the second sleeve. A bias member, such as a coil spring, isarranged to urge the second sleeve proximally against the inner sleeveand the inner sleeve against the plunger. With this arrangement, theinner channel is defined by the plunger, an inner surface of the innersection member and the inner surface of the inner sleeve. The outerchannel is defined by an outer surface of the inner section member, theouter surface of the inner sleeve, the inner surface of the secondsleeve, and an inner surface of the outer section member.

The latch bracket can further include a locking mechanism that inhibitsthe latch pin from retracting out from the latch bracket while fluidpressure is applied through the latch pin to the latch bracket. Thelocking mechanism can include a shuttle valve having first and secondinlets coupled to the inner and outer channels, respectively, and anoutlet. The locking mechanism also includes an outer sleeve arrangedadjacent a middle section of the body, which is located between the endcap and the cylindrical bearing. The outer sleeve and the middle sectiondefine an annular chamber coupled therebetween. The outer sleeve has aninner cylindrical surface having a diameter approximately the diameterof the cylindrical bearing to receive a distal end of the latch pin. Afluid channel connects between the shuttle valve outlet and a distal endof the chamber. An annular shaped locking block located within theannular chamber is arranged to slide longitudinally therein to aproximal position when fluid pressure is applied to the chamber throughthe outlet. A plurality of locking members are arranged to extendradially inward from the inner cylindrical surface of the outer sleevewhen the locking block moves to the proximal position. This engages thelocking members in an annular groove formed on an outer surface of thelatch pin.

The latch bracket can further include a fluid switch between the innerchannel and the outer channel that is closed circuit when the latch pinis connected to the latch bracket to equalize pressures between theinner channel and the outer channel, and that is open circuit when thelatch pin is connected to the latch bracket to allow for pressuredifferences between the inner channel and the outer channel.

In still another aspect, the invention provides a multi-line, rotatablefluid connector assembly, which includes a first part removably androtatably connectable to a second part. Each of the first and secondparts includes a plurality of fluid channels. Each of the plurality offluid channels is adapted to connect to a corresponding fluid channel ofthe other of the first and second parts. Each of the plurality of fluidchannels of each of the first and second parts includes an end sealarranged to inhibit fluid from spilling therefrom. The plurality offluid channels of the first part, the second part, or both the first andsecond parts are arranged concentrically.

In another aspect, the invention provides a multi-line fluid connector,including first and second parts removably connectable with each other.The first and second parts each includes a plurality of fluid channels.

Each of the plurality of fluid channels is adapted to connect to acorresponding fluid channel of the other of the first and second partswhen the first part is connected to the second part. Each fluid channelincludes a respective end seal. The first part and the second part arecooperatively structured to provide a make-before-break connectionbetween their respective corresponding fluid channels.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of a tool coupler according to theinvention on the end of an arm positioned to engage a hydraulic grapple.

FIG. 2 is a side elevation view of the tool coupler of FIG. 1 attachedto the hydraulic grapple.

FIG. 3 is a top plan view of the tool coupler of FIG. 1, shown detachedfrom the arm and with its latch pin in a retracted position. A matingportion of the tool that receives the latch pin is partially shown in abroken away view.

FIG. 4 is a view similar to that of FIG. 3, illustrating the latch pinin the connected position.

FIG. 5 is a longitudinal section view along line 5—5 of FIG. 3,illustrating a multi-line hydraulic coupling according to the invention.A latch pin and a latch bracket are shown in an unlatched position.

FIG. 6 is an end view of the latch pin end cap viewed from line 6—6 ofFIG. 5. Internal features are shown in shadow.

FIG. 7 a side view of the latch pin plug.

FIG. 8 is an end view of the latch pin plug viewed along line 8—8 ofFIG. 7.

FIG. 9 is a longitudinal sectional view of the latch pin inner sleeve.

FIG. 10 is a longitudinal sectional view of the latch pin outer sleeve.

FIG. 11 is a distal end view of latch bracket end section.

FIG. 12 is a sectional view through line 12—12 of FIG. 5 showing thedistal end section of the latch bracket in isolation.

FIG. 13 is a longitudinal sectional view of the latch bracket backingpiece.

FIG. 14 is an end view of the backing piece along line 14—14 of FIG. 13.

FIG. 15 is a distal end view of the latch bracket outer sleeve.

FIG. 16 is a section view through line 16—16 of FIG. 15.

FIG. 17 is a longitudinal section view of the latch bracket middlesleeve.

FIG. 18 is a longitudinal section view of the latch bracket innersleeve.

FIGS. 19-22 are sequential longitudinal section views illustrating thelatch pin connecting with the latch bracket to form two fluidconnections. FIG. 19 shows the latch pin initiating contact with theplunger of the latch bracket. FIG. 20 shows the first coaxial sealexchange. FIG. 21 shows the second coaxial seal exchange. FIG. 22 showsthe completed connection.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a quick-connect tool coupler 10 is attached to adipper stick 12 of a construction equipment, which can be a backhoe, anexcavator and the like. Tool coupler 10 can be rotated about a dipperpivot 14 by actuating a bucket cylinder 16, which is coupled by alinkage 18 to a link pivot 20 at a forward end of tool coupler 10. Alatch mechanism 21 (FIG. 3) in tool coupler 10 for connecting to a toolis structured substantially the same as the latch mechanisms ofquick-disconnect tool couplers described in co-owned U.S. Pat. No.5,727,342, the entire disclosure of which is included herein byreference. A detailed description of the latch mechanism in this type oftool coupler is provided in that patent, and therefore only a briefdescription will be provided here.

In FIG. 1, tool coupler 10 is positioned to engage a hydraulic grapple22. To engage tool coupler 10 with grapple 22, an operator maneuvers apair of crescent-shaped hooks 24 (only one shown) depending from toolcoupler 10 to engage a cross bar 26 on the upper end of grapple 22. Theoperator then extends bucket cylinder 16 to rotate tool coupler 10counter-clockwise as shown in FIG. 2. Referring now also to FIG. 3, thisstep aligns a latch pin 28 in tool coupler 10 with a latch bracket 30 ongrapple 22. Latch pin 28 is held in this retracted position by a latchcylinder 32, which has its rod 34 extended against a latch pin bearing36. The operator then releases hydraulic pressure in latch cylinder 32,which allows a coil spring 38 to slide latch pin 28 through latch pinbearing 36 and into engagement with latch bracket 30 as illustrated inFIG. 4. These steps are carried out in reverse order to release grapple22.

Grapple 22 includes a pair of jaws 40A, 40B that are opened and closedby actuating a hydraulic grapple cylinder 42. Latch pin 28 and latchbracket 30 form a two-part, nonspill, hydraulic fluid connector in atwo-line fluid circuit bringing controlled hydraulic pressure to grapplecylinder 42. A first pair of hydraulic fluid lines 44A, 44B connectbetween the hydraulic controls in the equipment and fittings inserted inports of a latch pin head 46 on a proximal end of latch pin 28. A secondpair of hydraulic fluid lines 48A, 48B couple between latch bracket 30and grapple cylinder 22. The fluid connector includes two separate andsubstantially coaxial flow paths in each of latch pin 28 and latchbracket 30.

The term “nonspill” as used herein refers to a sealing system wherein,for each flow path, a seal at the end of the flow path of one of thelatch pin or latch bracket slides over to provide a seal with a portionof the other of the latch pin or latch bracket before the seal at theend of the corresponding flow path in the other of the latch pin orlatch bracket opens to establish the fluid connection. In disconnectingthe latch pin from the latch bracket, the seal at the end of the otherof the latch pin or latch bracket flow path is reestablished before thesliding seal moves back. In this way, fluid is inhibited from leakingout of the system. This is also called a “make before break” type ofconnection. As will be described below with reference to the drawings,there is a dual seal within each fluid passageway. Each portion of theconnector has seals that close fluid lines when the components are notconnected and which resist spilling when making the connection.

The construction of the latch pin 28 will now be described withreference to FIG. 5, which will be followed by a description of thelatch bracket 30. Latch pin 28 includes an elongated, tubular latch pinbody 50 that is connected, for example, by a continuous weld, at aproximal end to latch pin head 46. The terms “proximal” and “distal” asused with reference to a described item will refer respectively to theright and the left sides of that item as viewed in FIG. 5. Latch pinbody 50 has a diameter of about 2.5 inches and a length of about 7.5inches. Latch pin head 46 includes two boss ports 52A, 52B for couplingto respective hydraulic fluid lines 44A, 44B. Boss ports 52A, 52B areshown angularly displaced from their actual positions for clarity inFIG. 5. Their relative positions are shown more accurately in FIG. 6.Boss ports 52A, 52B receive fittings that connect to respectivehydraulic lines 44A, 44B. Each of boss ports 52A, 52B communicates via arespective connecting channel 54A, 54B with a central opening 56extending through latch pin body 50 and partially through latch pin head46 from a distal end of latch pin 28. A surface of central opening 56includes a cylindrical proximal portion 58 within latch pin head 46 thathas a smaller radius than a distal portion 60 that extends toward thedistal end of central opening 56. A tube 62 inserted into centralopening 56 has an outer surface 63 at a proximal end that closely fitsadjacent to cylindrical proximal portion 58. An o-ring 64, positioned inan o-ring groove 65 in tube outer surface 63, provides a proximal sealbetween tube 62 and cylindrical proximal portion 58 of the surface ofcentral opening 56. The seal provided by o-ring 64 separates theinterior of latch pin 28 into separate fluid channels 101, 102 as willbe described in greater detail below.

Latch pin head 46 also includes a bore hole 66 threaded to receive latchpin cylinder 32. A set screw (not shown) is threaded into a tapped sidehole 68 to hold latch pin cylinder 32 in place. A recess 70 on theproximal side of latch pin head 46 receives and retains one end of coilspring 38 (See FIGS. 3 and 4).

Tube 62 extends about 80% of the length of latch pin body 50. One sideof a washer 72 rests against a distal facing shoulder 74 formed by aninner surface 75 of tube 62. One end of an inner coil spring 76 pressesagainst the other side of washer 72. Referring now also to FIGS. 7-9,the distal end of coil spring 76 presses against a proximal end surface77 of a plug 78. Plug 78 has tapered sides 79 and is retained by adistal end of an inner sleeve 80, which has an inwardly tapered portion81 of an inner surface fitting against tapered sides 79 of plug 78. Theinner surface of inner sleeve 80 also has a cylindrical distal portion82 that slides over a cylindrical distal surface 83 of plug 78. Ano-ring 84, positioned in an o-ring groove 84A in cylindrical distalportion 82 of the inner surface of inner sleeve 80, provides a sealbetween plug 78 and inner sleeve 80 at surfaces 82, 83.

Inner sleeve 80 further includes a cylindrical proximal inner surface 85adapted to slide over a cylindrical distal outer surface 86 of tube 62.Another o-ring 87 provides a seal between distal outer surface 86 oftube 62 and proximal inner surface 85 of inner sleeve 80. o-ring 87 ispositioned in an o-ring groove formed in distal outer surface 86 of tube62. In the described embodiment, a small aperture 87A that extendsradially through inner sleeve 80 is located a short distance from thedistal end of tube 62, just distally of o-ring 87.

An outer coil spring 88 has a proximal end positioned against a distalfacing shoulder 89 formed by an inner surface 89A of latch pin body 50.The distal end of coil spring 88 bears against a proximal facingshoulder 90 formed on an outer surface 90A of inner sleeve 80. Thedistal end of outer surface 90A of inner sleeve 80 has an inwardlytapered portion 91. Referring now also to FIG. 10, an outer sleeve 92has an inner surface including a central tapered portion 93 that engagestapered portion 91 of the outer surface of inner sleeve 80. Outer sleeve92 is held in place by a snap ring 94 that fits in an annular grooveformed in latch pin body 50. One o-ring 95, which sits in an o-ringgroove 95A, provides a seal between a cylindrical distal portion 96 ofthe inner surface of outer sleeve 92 and a cylindrical distal portion 97of an outer surface of inner sleeve 80. Another o-ring 98, positioned ino-ring groove 98A, provides a seal between an outer surface 99 of outersleeve 92 and a cylindrical distal portion 100 of surface 89A of latchpin body 50. The distal surfaces of plug 78, inner sleeve 80, outersleeve 92 and latch pin body 50 together provide a substantially flatend surface of latch pin 28 when latch pin 28 is in a retracted positionwithin tool coupler 10. By this arrangement, snap ring 94 retains outersleeve 92, which retains inner sleeve 80 against the spring forceexerted against it by outer coil spring 88. Inner sleeve 80 retains plug78 against the spring force exerted against it by inner coil spring 76.

This arrangement also provides two substantially concentric fluidchannels within latch pin 28. A central fluid channel 101 is coupled ata proximal end to boss port 52A through connecting channel 54A. Centralchannel 101 extends through the space inside tube 62, and through thespace inside inner sleeve 80 to plug 78, where o-ring 84 provides an endseal. An outer fluid channel 102 couples to boss port 52B throughconnecting channel 54B. Outer channel 102 then extends distally throughthe annular space between outer surface 63 of tube 62 and inner surface89A of latch pin body 50, and through the annular space between outersurface 90A of inner sleeve 80 and inner surface 89A of latch pin body50 to outer sleeve 92, where o-rings 95 and 98 provide end seals.O-rings 64 and 87 provide seals between central channel 101 and outerchannel 102. Central and outer channels 101, 102 are weakly connectedthrough aperture 87A in inner sleeve 80, which ensures that thepressures will be equalized between inner and outer channels 101, 102when tool coupler 10 is not connected to a tool.

As described above, latch pin 28 is extended distally by coil spring 38(FIG. 3) and retracted proximally by extending rod 34 of latch pincylinder 32. Latch pin bearing 36 restricts latch pin 28 to longitudinalmotion. Latch pin bearing 36 includes a latch pin bearing sleeve 104suitable for use as a slide bearing. Latch pin bearing 36 also includesan arcuate collar 106 on a distal end. Collar 106 is shaped to stopagainst an upper surface of latch bracket 30 so as to hold tool coupler10 in a proper lateral position for inserting latch pin 28 into latchbracket 30.

Latch bracket 30 includes three sections that are bolted together: aproximal end section 108 closest to the distal face of latch pin 28; amiddle section 110; and a distal end section 112. Latch bracket has anassembled length of about 6.6 inches and a diameter of about 4.5 inches.Proximal end section 108 has a body 114 extending through an aperture ina support plate 116 on grapple 22, and is welded or otherwise securedthereto. A cylindrical latch bracket bearing sleeve 118 positionedwithin a central bore of body 114 aligns with latch pin bearing sleeve104 when collar 106 is positioned against body 114 so as to receivelatch pin 28 in the extended and locked position.

Referring now also to FIGS. 11 and 12, distal end section 112 includes abody, or end cap 119, having an outer bore 120. Outer bore 120 has adiameter of about 2.72 inches and extends to a depth of about 0.314 inchfrom a proximal end face 121 of end cap 119. An annular groove 122 isformed concentrically within outer bore 120. Annular groove 122 has aninner diameter of about 1.409 inches, a width of about 0.188 inch, and adepth of about 0.188 inch from a bottom surface 123 of outer bore 120. Adeeper segment 124 of annular groove 122 is formed to an additionaldepth of about 0.745 inch. A central inner bore 126 has a diameter ofabout 0.688 inch and extends to a depth of about 0.927 inch from bottomsurface 123 of outer bore 120. The center of inner bore 126 includes atapped bore 128 that is tapped with a {fraction (5/16)}-18 thread about0.62 inch deep. An elongated plunger 129, screwed into tapped bore 128or otherwise secured at the bottom of inner bore 126, extends throughinner bore 126 and out past middle section 110 of latch bracket 30.

Four bolt holes 130 are provided for assembling distal end section 112with the other two sections of latch bracket 30. Similarly arranged boltholes (not shown) are provided in a middle section body 131 and proximalend section body 114. The bolt holes in proximal end section body 114may be threaded or may be clear holes with recessed areas on a proximalside to receive nuts.

Two boss ports 132A, 132B extend diametrically into end cap 119. Bossports 132A, 132B receive fittings that connect to respective hydrauliclines 48A, 48B. Boss port 132A is in fluid communication with inner bore126 via one connecting channel 134A, and boss port 132 b is in fluidcommunication with deeper segment 124 of annular groove 122 via anotherconnecting channel 134B. Secondary connecting channels 136A, 136Bconnect between respective boss ports 132A, 132B and end ports of ashuttle valve 139 (see FIG. 5), positioned within a side chamber 138.Shuttle valve 139 allows fluid flow from the higher pressure of its endports to a middle port. In the described embodiment, shuttle valve 139is a model LS04-B30 ball-type, screw-in shuttle valve, available fromHydra Force, Inc. of Lincolnshire, Ill. A third channel 140 extendslongitudinally from the middle port of shuttle valve 139 to proximal endface 121 to connect with another longitudinal channel 164 in middlesection body 131 as will be described below.

Referring now also to FIGS. 13 and 14, a backing piece 142 is locatedwith its distal end face 144 adjacent bottom surface 123 of outer bore120 of end cap 119. Backing piece 142 includes a central opening 146, asubstantially annular shaped inner section 148 centered on centralopening 146, and a substantially annular shaped outer section 150coaxial with inner section 148. Inner and outer sections 148, 150 areconnected by supporting members 152 defining a ring of circularapertures 154 located between inner and outer sections 148, 150. Backingpiece 142 is held against end cap 119 by a coil spring 193, whichpresses against a proximal facing surface 155 of outer section 150. Ascan be seen in FIG. 5, there is a small radial gap 153, e.g. about{fraction (1/32)} inch, between outer section 150 of backing piece 142and a cylindrical surface of end cap 119. This permits backing piece 142to move a small lateral distance within end cap 119.

Central opening 146 communicates with central bore 126 of distal endsection 112, while apertures 154 communicate with annular groove 122 anddeeper section 124 of distal end section 112. An outer o-ring 156, whichis positioned in an outer o-ring groove 157, provides a seal between endcap 119 and backing piece 142 outside the diameters of outer opening 154and annular groove 122. An inner o-ring 158, positioned in an innero-ring groove 159, provides a seal between end cap 119 and backing piece142 inside the ring of apertures 154 and the diameter of annular groove122 and outside the diameters of central bore 126 and central opening146.

Middle section body 131 has a central opening defined by a stepped innersurface 133. A substantially annular-shaped locking ring 160 ispositioned in an outer step 162. Longitudinal channel 164 extends fromouter step 162 through to a distal end of middle section 110, and isaligned with channel 140 in distal end section 112. An o-ring 165between middle section body 131 and end cap 119 provides a seal aroundthe connection between channels 140, 164. O-ring 166 provides a sealbetween locking ring 160 and surface 133.

Referring now also to FIGS. 15 and 16, an outer sleeve 168 is positionedin an inner step of surface 133 adjacent to locking ring 160. Outersleeve 168 includes a cylindrical inner surface 170 providing a centralopening 172. An outer surface includes a cylindrical distal portion 174,a central outwardly sloped portion 176, and a proximal cylindricalportion 178. The outer surface of outer sleeve 168 and stepped surface133 of middle section body 131 define an annular shaped chamber 256connected at a distal end to longitudinal channel 164. Locking ring 160slides laterally when fluid pressure is applied to chamber 256 throughlongitudinal channel 164. O-ring 177 provides a seal between distalcylindrical surface 174 and surface 133 of middle section body 131.Another o-ring 179 provides a seal between distal cylindrical surface174 and an inner cylindrical surface of locking ring 160. O-rings 166,177, 179 seal chamber 256.

Spaced evenly around outer sleeve 168 at a juncture between cylindricaldistal surface 174 and outwardly sloped surface 176 are sixteen radiallyextending, tapered apertures 180, which are larger on an outer surfacethan on inner surface 172. Inside each aperture 180 is a ball bearing182. Locking ring 160 responds to fluid pressure in channel 164 bysliding in a proximal direction between step surface 162 and outersleeve 168. This causes an outwardly sloped proximal surface 183 oflocking ring 160 to push ball bearings 182 radially inward.

In the unlatched position shown in FIG. 5, ball bearings 182 contact aninwardly tapered outer rim 184 of a flange 185 on a middle sleeve 186.Referring now also to FIG. 17, which shows middle sleeve 186 inisolation, an outer surface of middle sleeve 186 includes a cylindricaldistal portion 188 in sliding contact with a cylindrical inner surface190 of a proximal end of outer section 150 of backing piece 142. Ano-ring 192 positioned in an o-ring groove 192A provides a seal betweensurfaces, 188 and 190, of middle sleeve 186 and backing piece 142,respectively. Middle sleeve 186 is urged in a proximal direction by coilspring 193, positioned between proximal facing surface 155 of backingpiece 142 and a distally facing surface 191 (FIG. 12) of flange 185 ofmiddle sleeve is 186.

Middle sleeve 186 in turn, is retained in position by an inner sleeve194, which is, in turn, held in position by plunger 129. Referring nowalso to FIG. 18, which shows inner sleeve 194 in isolation, an outersurface 195 of inner sleeve 194 includes an cylindrical distal portion196 in sliding contact with a cylindrical inner surface 198 of innersection 148 of backing piece 142. An o-ring 200 that sits in an o-ringgroove 197 in inner section 148 provides a seal between cylindricalsurface portions 198 and 196. In the described embodiment, a smallaperture 199 that extends radially through inner sleeve 194 is locatedjust proximally of inner section 148 of backing piece 142. An innersurface 201 of middle sleeve 186 has an outwardly sloped proximalportion 202 urged by spring 193 into contact with a similarly slopedproximal portion 204 of an outer surface 195 of inner sleeve 194 whenlatch bracket 30 is in the unlatched position shown in FIG. 5. This alsourges an outwardly sloped portion 206 at the proximal end of an innersurface 207 of inner sleeve 194 into contact with plunger 129 at asimilarly sloped portion 208 of an enlarged proximal end of a surface209 thereof. Sloped portion 208 of plunger surface 209 thus retainsinner sleeve 194 and middle sleeve 186 in place against the bias forceof spring 193, which urges these pieces proximally out of latch bracket30. One o-ring 210 that sits in an o-ring groove 211 in inner sleeve 194provides a seal between sloped surface portions 202, 204 of middle andinner sleeves 186, 194, respectively. Another o-ring 212 provides a sealbetween surfaces 206, 208 of inner sleeve 194 and plunger, respectively,and is located in an o-ring groove 213.

As is now apparent from the above description, latch bracket 30, likelatch pin 28, includes two substantially concentric fluid channels. Anannular inner fluid channel 214 is substantially defined by longitudinalsurface 209 of plunger 129, o-ring 212, inner surface 207 of innersleeve 194, o-ring 200, inner surface 198 of inner section 148 ofbacking piece 142, o-ring 158, and central bore 126 of distal endsection 112. Inner fluid channel 214 connects to hydraulic fluid line48A, as described above, through connecting channel 134A and boss port132A. A substantially annular outer fluid channel 216 is substantiallydefined by o-rings 156, 158, an outer surface 218 of inner section 148of backing piece 142, outer surface 195 of inner sleeve 194, o-ring 210,inner surface 201 of middle sleeve 186, o-ring 190, an inner surface 220of outer section 150 of backing piece 142, and annular groove 122 ofdistal end section 112. Outer channel 216 connects to hydraulic fluidline 48B 30 through connecting channel 134B and boss port 132B. In theunlatched configuration illustrated in FIG. 5, inner and outer channels214, 216 of latch bracket 30 are weakly connected through aperture 199in latch bracket inner sleeve 194. This feature equalizes the pressurebetween inner and outer channels 214, 216 when latch bracket 30 isunconnected from latch pin 28.

To assemble latch pin 28, latch pin body 50 is first fastened to latchpin head 46. Tube 62, with o-rings 64, 87 each positioned in respectiveo-ring grooves 65, 87A, is fully inserted within pin body 50 so that itabuts the proximal end of central opening 56. With latch pin head 46resting on its proximal end, washer 72 is dropped into tube 62 so thatwasher 72 rests upon shoulder 74. Inner coil spring 75 is dropped intotube 62, such that it is supported by washer 72. Outer coil spring 88 isthen dropped into latch pin body 50 central opening 56 over tube 62 sothat outer coil spring 88 rests on shoulder 89 of inner surface 89A oflatch pin body 46. Plug 78, inner sleeve 80 and outer sleeve 92 areassembled separately, with o-rings 84, 95, 98 positioned in respectiveo-ring grooves 84A, 95A, 98A. The sub-assembly of plug 78, inner sleeve80 and outer sleeve 92 is then positioned within central opening 56 oflatch pin body 50. In this manner, proximal end surface 77 of plug 78contacts inner coil spring 76, inner surface 85 of inner sleeve 80 ispositioned to slide over cylindrical distal outer surface 86 of tube 62,shoulder 90 of inner sleeve contacts outer coil spring 88, and outersleeve 92 is positioned concentric to inner sleeve 80. After pushing thesub-assembly of plug 78, inner sleeve 80, and outer sleeve 92 intoposition, snap ring 94 is inserted to retain the sub-assembly in placeagainst the forces exerted by springs 76, 88.

Latch bracket 30 is assembled in the following manner. Distal end cap112 is turned so that center bore 126 is exposed. O-rings 156, 158, 192,and 200 are positioned within respective o-ring grooves 157, 159, 192A,197 of backing piece 142, which is then positioned within the opening ofend cap 112. Coil spring 193 is then positioned on surface 155 ofbacking piece 142 and middle sleeve 186 is positioned on spring 193 andinside outer section 150 of backing piece 142. Inner sleeve 194 is thenplaced inside middle sleeve 186 and inner section 148 of backing piece142. Plunger 129 is then inserted inside inner sleeve 194. Spring 193 iscompressed by screwing the distal end of plunger 129 into threaded bore128 of end cap 112. Sloped portion 208 of plunger surface 209 contactssloped portion 206 of inner surface 207 of inner sleeve 194 when plunger129 is positioned properly.

Latch bracket middle section 110 is assembled by the following steps.First, o-ring 177 is positioned in the appropriate o-ring groove ofmiddle section body 131 and o-rings 166, 179 are positioned in theirrespective o-ring grooves of locking ring 160. Locking ring 160 is thenslipped over outer sleeve 168, leaving a gap between surface 183 oflocking ring 160 and surface 176 of outer sleeve 168. With outer sleeve168 standing on its distal end, ball bearings 182 are then dropped intothe gap until each is positioned in one of tapered apertures 180.Locking ring 160 is next moved up proximally against ball bearings 180to hold them in place. The assembly consisting of locking ring 160,outer sleeve 168 and ball bearings 180 is then inserted into middlesection body 131 until the distal end of outer sleeve 168 butts upagainst a step formed in inner surface 133 of middle section body 131.

To complete assembly of latch bracket 30, bolts (not shown) are insertedthrough bolt holes 130 in end cap 119 and distal end section 112 ispositioned upright on its distal end. Middle section body 131 is placedon end cap 119 with channels 140, 164 aligned, such that the boltsextend through appropriately placed bolt holes (not shown) in middlesection body 114. Proximal end section 108 is then placed on top ofmiddle section 110 such that the bolts fit into respective bolt holes(not shown) in proximal end section 108, and the assembly is secured bytightening the bolts.

In the unlatched position shown in FIG. 5 each of central and outerfluid channels 101, 102 of latch pin 28 are sealed at a distal end oflatch pin 28, even when positive fluid pressure is applied in thesechannels 101, 102. Also, each of inner and outer fluid channels 214, 216of latch bracket 30 are sealed at a proximal end, and remain closed evenwhen some residual fluid pressure remains in latch bracket 30. As willbe described below, when latch pin 28 and latch bracket 30 are fullyconnected together, central fluid channel 101 of latch pin 28 and innerfluid channel 214 of latch bracket 30 are coupled together in fluidcommunication, and outer fluid channel 102 of latch pin and outer fluidchannel 216 of latch bracket 30 are coupled in fluid communication witheach other. The connection is made in a non-spill manner, such thathydraulic fluid does not leak from either latch pin 28 or latch bracket30 at any time during the connection process. Seals are maintained toinhibit fluid leaking out from any of the channels or from cross-leakingbetween channels when latch pin 28 and latch bracket 30 are in a coupledposition.

The operation of the latching mechanism will now be described withreference to FIGS. 5 and 19-22. Normally, hydraulic pressure will bereleased from fluid channels 101, 102 prior to coupling. Some residualfluid and pressure may remain in either or both fluid channels 101, 102.This pressure would be equalized by a small flow through aperture 87A inthe described embodiment. Similarly, any residual pressure that may beleft in channels 214, 216 in latch bracket 30 would be equalized by flowthrough aperture 199.

When hydraulic pressure in latch pin cylinder 32 is released, spring 38moves latch pin 28 very quickly through bearing sleeves 104, 118, froman unconnected position shown in FIG. 5 to a locked position shown inFIG. 22. Referring first to FIG. 19 and also referring again to FIG. 5,after latch pin 28 has traveled through most of proximal end section 108of latch bracket 30, a distal end face 222 of plug 78 makes firstcontact with a proximal end face 224 of plunger 129. As latch pin 28continues to move distally into latch bracket 30, plug 78 is stoppedfrom further movement by plunger 129, which is rigidly attached to endcap 119. However, the remainder of latch pin 28 continues to movedistally into middle section 110.

As seen best in FIG. 20, cylindrical distal portion 82 of the innersurface of inner sleeve 80 of latch pin 28 has a diameter just largeenough to slide over a cylindrical outer surface 226 of a proximal endof inner sleeve 194 of latch bracket 30. As inner sleeve 80 of latch in28 slips over inner sleeve 194 of latch bracket 30, plug 78 is pushedproximally deeper into latch pin 28 by plunger 129 working against thebias force of inner coil spring 76. This also causes o-ring 84 to slideoff cylindrical distal outer surface 83 of plug 78 and onto cylindricalouter surface 226 of inner sleeve 194 in a continuous manner such thatthe seal at the end of central channel 101 does not leak.

When a distal end face 228 of latch pin inner sleeve 80 reaches aproximal facing surface 230 of latch bracket inner sleeve 194, innersleeve 80 is stopped from further movement. Referring now also to FIG.21, latch pin 28 has moved beyond inner section 108 of latch bracket 30and into middle section 110. Cylindrical distal portion 96 of the innersurface of latch pin outer sleeve 92 has a diameter slightly larger thana cylindrical proximal outer surface 232 of latch bracket middle sleeve186. This allows latch pin outer sleeve 90 to slide over middle sleeve186 while o-ring 95 continuously maintains a seal at the end of outerchannel 102. Meanwhile, tube 62 slides inside latch pin inner sleeve 80,as o-ring 87 maintains the seal between their respective outer and innersurfaces 86, 85. Note that aperture 87A is now located proximally ofo-ring 87, so that central channel 101 is sealed off from outer channel102.

As latch pin 28 continues to move distally into latch bracket 30, adistal end face 234 of latch pin body 50 and a distal end face 236 ofouter sleeve 92 both make contact with a proximal facing surface 238 ofmiddle sleeve 186 of latch bracket 16. A beveled distal corner 240 oflatch pin body 50 also makes contact with balls 182. Central and outerchannels 101, 102 in latch pin 28 remain closed through this point, asdo inner and outer channels 214, 216 in latch bracket 30. Coil springs76, 88 in latch pin 28 have both been compressed, but coil spring 193,which is a much heavier spring than coil springs 76, 88, has not beencompressed to any significant degree.

Latch pin 28 continues to slide distally into latch bracket 30 under theforce of coil spring 38, moving between the position shown in FIG. 21and the position shown in FIG. 22, which is a terminal position. Latchpin body 50 and latch pin outer sleeve 92 push latch bracket middlesleeve 186 distally against the countering bias force of spring 193. Asmiddle sleeve 186 is pushed back, outer spring 88 in latch pin 28 forceslatch pin inner sleeve 80 to push latch bracket inner sleeve 194 backalong with middle sleeve 186. This moves latch bracket inner sleeve 194back and away from plunger 129, closing the fluid circuit betweencentral channel 101 in latch pin 28 and inner channel 214 in latchbracket 30. Plug 78 includes flutes 242 cut into a proximal end tobetter enable fluid flow around plug 78 from central channel 101 toinner channel 214 (see, also, FIGS. 7 and 8). In addition, plug 78includes a circular ridge 243 on a proximal side that helps to keepinner coil spring 76 centered on plug 78 and plug 78 centered on plunger129. At this point, outer fluid channel 102 in latch pin 28 is stillsealed, as is outer fluid channel 216 in latch bracket 30.

Latch bracket inner sleeve 194 slides distally within inner section 148of backing piece 142 until a distal end 244 of inner sleeve 194 reachesbottom surface 133 of outer bore 120 of end cap 119. At some time inthis travel, aperture 199 moves to the distal side of o-ring 200, whichcloses off the small passageway provided by aperture 199 between innerand outer channels 214, 216 in latch bracket 30.

This also prevents further movement of latch pin inner sleeve 80, buttube 62 continues to slide distally within inner sleeve 80 as latch pin28 continues moving. Latch pin 28 also continues to push middle sleeve186 distally until distally facing surface 191 of flange 185 moves closeto a proximal end 246 of backing piece 142. At this point, as shown inFIG. 22, a proximal end 248 of latch pin inner sleeve 80 is close to ashoulder 250 formed on an outer surface 252 of tube 62. In addition,latch pin body 50 has slid deep enough into latch pin bracket 30 suchthat balls 182 can move into an annular groove 254 formed on an outersurface of latch pin body 50.

The continued movement of middle sleeve 186, while at the same timeinner sleeve 194 is stopped, opens the seal provided by o-ring 210between inner sleeve 194 and middle sleeve 186. This closes the fluidcircuit between outer fluid channel 102 in latch pin 28 and outer fluidchannel 216 in latch bracket 30. Now both fluid circuits are connected,with central channel 101 in fluid communication with inner channel 214and outer channel in fluid communication with outer channel 216, andgrapple 22 is secured to tool coupler 10.

Latch mechanism 21 includes a hydraulic locking mechanism that inhibitsrelease of latch pin 28 when fluid pressure is applied to the attachedtool through the fluid connector. Locking ring 160 is free to slidelongitudinally in annular chamber 256 provided between latch bracketouter sleeve 168 and middle section body 131. Shuttle valve 139 reactsto fluid pressure in either of channels 214, 216 by permitting fluidfrom the higher pressure side to flow into channel 140. Channel 140 isin fluid communication with longitudinal channel 164, which is in fluidcommunication with annular chamber 256. O-rings 166, 177, 179 provideseals inhibiting the fluid from leaking out of annular chamber 256.Fluid pressure in annular chamber 256 causes locking ring 160 to slideproximally to the end of annular chamber 256. This causes a slopedproximal surface 258 of locking ring 160 to push balls 182 radiallyinward into annular groove 254 of latch pin body 50 and holds them thereunder the applied hydraulic pressure. Thus, so long as hydraulicpressure is applied through at least one of the fluid channels in theconnector, latch pin 28 is inhibited from being accidentallydisconnected from latch bracket 28, which could release grapple 22 orother tool from tool coupler 10. Moreover, fluid pressure is maintainedin grapple 22, preventing accidental release of material being held bygrapple 22. For both these reasons, the locking feature provides anadded measure of safety for ground personnel working near the equipmentto which the tool is attached.

The described connector is designed so that it does not require perfectalignment between latch pin 28 and latch bracket 30. Latch pin 28 issubstantially well aligned with latch bracket 30 before their internalparts begin to couple because of the close fit between latch pin body 50and latch bracket bearing sleeve 118. Most lateral movement of latch pin28 is inhibited because of this fit. In addition, backing piece 142 hassome room to move laterally within gap 153. This permits the slidingparts, such as sleeves 80, 186, and 194, to align properly during theconnecting process. When a tool, such as grapple 22, is in use, therewill be some small lateral jostling of latch pin 28 within latch bracket30. Gap 153 provides some room for back piece 142 to also move, whichhelps maintain integrity of the seals within the connector.

To disconnect a tool, such as grapple 22, from tool coupler 10, theoperator first reduces hydraulic pressure in lines 44A, 44B, whichreduces hydraulic pressure in the attached tool. This also releasespressure in the hydraulic locking mechanism described above, permittinglatch pin 28 to be retracted from latch bracket 30. With the toolresting on the ground and bucket cylinder extended 16, the operatorapplies hydraulic pressure to latch cylinder 32. This extends rod 34against latch pin bearing 36, which is fixed to the frame of toolcoupler 10. Extending rod 34 moves latch pin head 46 (and the rest oflatch pin 28) proximally and counter to the bias force exerted by coilspring 38. As latch pin 28 is pulled back, spring 88 keeps latch bracketinner sleeve 194 in place against end cap 119, while latch bracketmiddle sleeve 186 follows latch pin 28 under the force exerted by coilspring 193. Sloped proximal portion 202 of inner surface 201 of middlesleeve 186 contacts sloped proximal portion 204 of outer surface 195 ofinner sleeve 194, and starts to push inner sleeve with middle sleeve186. O-ring 210 reseals outer channel 216 with contact between middlesleeve 186 and inner sleeve 194. Eventually, inner sleeve 194 is carriedproximally to make contact with plunger 129 again, and o-ring 212reseals inner channel 214. With latch pin 28 retracting further, latchpin outer sleeve 92 slides back over latch pin inner sleeve 80,reestablishing an end seal for outer fluid channel 102 with o-ring 95.Next, tapered portion 93 of the inner surface of outer sleeve 92contacts tapered portion 91 of the outer surface of inner sleeve 80, andouter sleeve 92 starts pulling inner sleeve 80 proximally with latch pinbody 50. Inner sleeve 80 slides back over plug 78, and o-ring 84 resealsthe distal end of central fluid channel 101.

With latch pin in the position shown in FIG. 19, latch bracket innersleeve 194 has slid proximally to a point where aperture 199 againprovides a connection between inner and outer fluid channels 214, 216 inlatch bracket. Similarly, latch pin inner sleeve 80 has moved to aposition where aperture 87A communicates between central and outer fluidchannels 101, 102 in latch pin 28. All fluid channels are sealed in bothlatch bracket 30 and latch pin 28 such that fluid cannot leak out.

At this point, latch pin 28 is still within latch bracket 30, and so thetool is still securely attached to tool coupler 10. When latch pin 28 isfully withdrawn from latch bracket 30, the operator can rotate toolcoupler 10 away from the tool and disengage hooks 24, as described inU.S. Pat. No. 5,727,342.

It is apparent from the above description that latch pin 28 and latchbracket 30 would be capable of rotating relative to each other abouttheir common longitudinal axis were they not attached to tool coupler 10or grapple 22, respectively. Both latch pin 28 and latch bracket 30 havea high degree of rotational symmetry about their common central axis.Central and outer channels 101, 102 in latch pin body 50 aresubstantially concentric throughout their lengths. Similarly, inner andouter channels 214, 216 in latch bracket 30 are also substantiallyconcentric. O-rings 64, 84, 87, 95, 190 and 200 are all concentric withthe central axis, and permit relative rotation of the parts that theyrespectively seal. Ball bearings 182 enable latch pin body 50 to rotaterelative to latch bracket 30. Moreover, most internal surfaces arebathed in hydraulic oil, which lubricates moving parts.

This rotational capability allows, the invention to provide a rotatable,multi-line fluid connector. The described connector can be employed in acoupling mechanism to a rotatable tool, such as a rotatable hanginggrapple. The rotation feature can be enhanced by inserting bearing ringsin strategic locations, such as between washer 47 and shoulder 72,between coil spring 193 and flange distal facing surface 191 of latchbracket middle sleeve 186, and between coil spring 88 and shoulder 248of latch pin body 50.

While in the above described embodiment the hydraulic grapple includes adouble action hydraulic cylinder 42, the described tool coupler 10 canalso be employed to engage tools having one or more single actionhydraulic cylinders or tools having no hydraulic cylinders. Whenemploying a tool with one single action cylinder, a plug would beinserted in one of ports 52A, 52B, and the other of ports 52A, 52B onlatch bracket 30 would be connected to the hydraulic cylinder. Tools nothaving any hydraulics could include a latch bracket without hydraulicconnector parts, as described in U.S. Pat. No. 5,727,342, instead oflatch bracket 30.

It should also be understood that the fluid connecting parts in latchpin 28 can be incorporated into latch bracket 30, and the fluidconnecting parts in latch bracket can be incorporated into latch pin 28.For example plunger 129, latch bracket inner sleeve 194, latch bracketmiddle sleeve 186 and backing piece 142 could be located in a latch pin,while plug 78, tube 62, pin inner sleeve 80 and pin outer sleeve 92could be incorporated into a latch bracket.

It will be apparent to those of skill in the art that the abovedescribed embodiment of a multi-line fluid connector, which includes twofluid lines, is constructed with features that are applicable to thedesign and construction of fluid connectors with more than two fluidlines according to the invention. Among these features are concentricfluid lines, make-before-break seals, and spring assisted closures.

The multi-line fluid connector of the invention can be used in couplershaving a latching member that is different from a cylindrical latch pin.The multi-line fluid connector can be employed in fields outside of theconstruction equipment industry, and with fluids other than hydraulicfluids.

Other embodiments are within the scope of the following claims.

What is claimed is:
 1. A latch bracket for attachment to a hydraulicallyoperated tool having a hydraulic mechanism, the latch bracket comprisinga first fluid channel extending therethrough, a first port coupled tothe first fluid channel for coupling the first fluid channel to thehydraulic mechanism, wherein the latch bracket is adapted to receive amale latch pin on a tool coupler to lock the tool to the tool couplerand to couple the first fluid channel to a source of hydraulic pressurethrough the latch pin.
 2. The latch bracket of claim 1, furthercomprising a second fluid channel extending through the latch bracketand a second port coupled to the second fluid channel for coupling thesecond fluid channel to the hydraulic mechanism, wherein the latchbracket is further adapted to couple the second fluid channel to asecond source of hydraulic pressure through the latch pin.
 3. The latchbracket of claim 2, wherein the second fluid channel comprises an outerfluid channel concentrically surrounding the first fluid channel.
 4. Thelatch bracket of claim 3, wherein the first fluid channel comprises asubstantially annular inner fluid channel.
 5. The latch bracket of claim4, further comprising an inner proximal o-ring positioned to provide aseal at a proximal end of the inner channel of the latch bracket and anouter proximal o-ring positioned to provide a seal at a proximal end ofthe outer channel of the latch bracket when a latch pin is disconnectedfrom the latch bracket, the inner proximal o-ring and the outer proximalo-ring being arranged to unseal when a latch pin is connected to thelatch bracket.
 6. The latch bracket of claim 5, further comprising: abody, including a cylindrical bearing at a proximal end adapted toreceive and guide the latch pin, and an end cap at a distal end; anelongated plunger extending proximally from the body a first distance,including an outwardly sloped surface near a proximal end, and aproximal end face that first contacts a distal end of the latch pin whenthe latch pin is inserted into the cylindrical bearing, wherein theoutwardly sloped surface comprises an o-ring groove in which the innerproximal o-ring is positioned; a substantially annular inner sectionmember extending proximally from the body a second distance that is lessthan the first distance, wherein the inner section member includes acylindrical surface and is arranged substantially concentrically aroundthe plunger providing a gap therebetween; a substantially annular outersection member extending proximally from the body a third distance thatis less than the first distance and greater than the second distance,wherein the outer section member includes a cylindrical surface and isarranged concentrically around the inner section member providing a gaptherebetween; an inner sleeve, comprising: an inner surface having anoutwardly sloped portion at a proximal end adapted to fit against theoutwardly sloped surface of the plunger, the first proximal o-ringproviding a seal therebetween when the latch bracket is disconnectedfrom the latch pin; an outer surface having an outwardly sloped portionnear a distal end that includes an o-ring groove in which the outerproximal o-ring is positioned; and a cylindrical surface at a distal endthat slidingly engages with the cylindrical surface of the inner sectionmember, wherein the inner channel is defined by the plunger, an innersurface of the inner section member and the inner surface of the innersleeve; a inner middle o-ring providing a seal between the cylindricalsurface of the inner section member and the cylindrical surface of thebracket inner sleeve; a second sleeve, comprising: an inner surfacehaving an outwardly sloped portion at a proximal end adapted to fitagainst the outwardly sloped surface of the outer surface of the innersleeve, the outer proximal o-ring providing a seal therebetween when thelatch bracket is disconnected from the latch pin; and a cylindricalsurface at a distal end that slidingly engages with the cylindricalsurface of the inner section member, wherein the outer channel isdefined by an outer surface of the inner section member, the outersurface of the inner sleeve, the inner surface of the second sleeve, andan inner surface of the outer section member; an outer middle o-ringarranged to seal between the cylindrical surface of the outer sectionmember and the cylindrical surface of the second sleeve; and a biasmember arranged to urge the second sleeve proximally against the innersleeve and the inner sleeve against the plunger.
 7. The latch bracket ofclaim 6, further comprising a locking mechanism that inhibits the latchpin from retracting out from the latch bracket while fluid pressure isapplied through the latch pin to the latch bracket.
 8. The latch bracketof claim 7, wherein the locking mechanism includes: a shuttle valvehaving first and second inlets coupled to the inner and outer channels,respectively, and an outlet; an outer sleeve arranged adjacent a middlesection of the body which is located between the end cap and thecylindrical bearing, the outer sleeve and the middle section defining anannular chamber coupled therebetween, the outer sleeve comprising aninner cylindrical surface having a diameter approximately the diameterof the cylindrical bearing to receive a distal end of the latch pin; afluid channel connecting between the outlet and a distal end of thechamber; an annular shaped locking block within the annular chamber thatis arranged to slide longitudinally therein to a proximal position whenfluid pressure is applied to the chamber through the output; and aplurality of locking members arranged to extend radially inward from theinner cylindrical surface of the outer sleeve when the locking blockmoves to the proximal position to engage the locking members in anannular groove formed on an outer surface of the latch pin.
 9. The latchbracket of claim 2, further comprising a fluid switch between the firstfluid channel and the second fluid channel that closes when the latchpin is connected to the latch bracket to equalize pressures between thefirst fluid channel and the second fluid channel, and that opens whenthe latch pin is connected to the latch bracket.
 10. The latch bracketof claim 6, further comprising a backing piece that includes the innersection member, the outer section member and an opening therebetween,wherein the backing piece is capable of moving a small lateral distancefrom a central axis of the latch bracket.